Dinosaurs were once found all over the earth. Now they are gone. They have all died out. No one is sure how this happened. Some scientists believe the weather changed. Some believe disease killed them all. All that we can be sure of is that once they lived.
恐龍曾遍布地球的每個角落，現(xiàn)在他們沒了，全部都滅絕了。沒有人確定這是怎么發(fā)生的。一些科學家認為氣候變了，還有一些認為是疾病導致它們滅絕。我們所能確定的就是它們曾經(jīng)生存過。
恐龍曾遍布地球的每個角落，現(xiàn)在他們沒了，全部都滅絕了。沒有人確定這是怎么發(fā)生的。一些科學家認為氣候變了，還有一些認為是疾病導致它們滅絕。我們所能確定的就是它們曾經(jīng)生存過。